TWI665463B - Scintillator panel, radiation image detection device and manufacturing method thereof - Google Patents

Abstract

An object of the present invention is to provide a highly reliable scintillator panel, which is capable of remarkably suppressing the scattering of light emitted from a phosphor by a simple method to obtain a light beam with sufficient intensity, thereby obtaining an image with excellent definition. The invention provides a scintillator panel comprising a substrate and a phosphor layer containing a phosphor powder. The surface of the phosphor layer has a plurality of depressions, and the area A of the depression opening is 500 to 70,000 μm ² . The ratio D / T of the thickness T of the photobody layer to the depth D of the depression is 0.1 to 0.9.

Description

Scintillator panel, radiation image detection device and manufacturing method thereof

The invention relates to a scintillator panel, a radiation image detection device and a manufacturing method thereof.

In the past, radiographic images using negative films have been widely used in medical facilities. However, since radiographic images using negatives are analog image information, digital radiation such as computer radiography (CR) or flat panel detector (hereinafter referred to as "FPD") has been developed in recent years. Image detection device.

FPD has a direct type and an indirect type. In the indirect type, a scintillator panel is used to convert radiation into visible light. The scintillator panel includes a phosphor layer containing a phosphor such as cesium iodide (CsI) or gadolinium sulfide (GOS) as a constituent element, and the phosphor emits visible light in response to the radiated radiation. The TFT or CCD is converted into an electronic signal, which converts radiation information into digital image information.

The method for forming the phosphor layer is a simpler method using a coating film of a paste-like phosphor powder as the phosphor layer. However, the light emitted by the phosphor inside the coating film is scattered, and the sharpness of the image is extremely low. Therefore, in order to suppress the scattering of light emitted by the phosphor, the light emission is efficiently used. For light, there are literature proposals: a method of alternately providing a phosphor layer composed of a large-sized phosphor and a phosphor layer composed of a small-sized phosphor (Patent Document 1); and providing a method for separating the phosphor layer Method of partition walls (Patent Documents 2 to 4); columnar crystal structure phosphors such as CsI are formed by vapor deposition, and the light emitted from the phosphors is guided to a TFT or CCD to improve S / N Method (Patent Documents 5 and 6) and the like.

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2003-215253

[Patent Document 2] Japanese Patent Laid-Open No. 5-60871

[Patent Document 3] Japanese Patent Laid-Open No. 2011-188148

[Patent Document 4] Japanese Patent Application Laid-Open No. 2011-007552

[Patent Document 5] Japanese Patent Laid-Open No. 2012-242355

[Patent Document 6] Japanese Patent Laid-Open No. 2013-117547

However, in the current situation, the method of alternately providing layers having different phosphor particle sizes or the method of providing a partition wall cannot sufficiently suppress the scattering of light emitted by the phosphor, and it is not possible to obtain a sufficient intensity of light. In addition, a method using CsI or the like with a columnar crystal structure as the phosphor layer is considered to have problems such as low chemical stability of the columnar crystal structure, or easy incorporation of foreign matter, thereby deteriorating panel image quality.

Therefore, an object of the present invention is to provide a highly reliable scintillator panel that significantly suppresses the phosphors by using a simple method. Scattering of the luminous light can obtain luminous light with sufficient intensity, and can obtain an image with excellent definition.

The above-mentioned problems can be achieved by any of the following technical means.

A scintillator panel is a scintillator panel including a substrate and a phosphor layer containing a phosphor powder, and the surface of the phosphor layer has a plurality of depressions, and the area A of the depression opening is 500 to 70,000 μm ² . The ratio D / T of the thickness T of the phosphor layer to the depth D of the depression is 0.1 to 0.9.

A radiation image detection device includes the scintillator panel.

A manufacturing method of a radiographic image detection device is a manufacturing method of a radiographic image detection device including the scintillator panel and a detection substrate provided with a photoelectric conversion element opposed to the depression of the scintillator panel. The method includes: (A) a step of matching the depression with the photoelectric conversion element, and (B) a step of bonding the scintillator panel and the detection substrate.

According to the present invention, it is possible to provide a scintillator panel with excellent reliability, which can significantly suppress the scattering of the luminous rays of the phosphors by using a simple method and ensure sufficient luminous rays, thereby realizing an image with extremely high definition.

1‧‧‧ radiation image detection device

2‧‧‧ scintillator panel

3‧‧‧ Inspection substrate

4‧‧‧ substrate

5‧‧‧ buffer layer

6‧‧‧ partition

7‧‧‧ phosphor layer

8‧‧‧Reflective layer

9‧‧‧ Adjacent layer

10‧‧‧ photoelectric conversion layer

11‧‧‧ output layer

12‧‧‧ substrate

13‧‧‧Power Supply Department

FIG. 1 is a cross-sectional view schematically showing a configuration of a radiographic image detection apparatus including one aspect of the scintillator panel of the present invention.

Fig. 2 is a perspective view schematically showing a configuration of one aspect of the scintillator panel of the present invention.

FIG. 3 is a cross-sectional view schematically showing a configuration of a radiographic image detection apparatus including a scintillator panel according to the present invention.

FIG. 4 is a cross-sectional view schematically showing a configuration of a radiographic image detection apparatus including a scintillator panel of the present invention.

Fig. 5 is a cross-sectional view schematically showing a configuration of a radiographic image detection apparatus including a scintillator panel according to the present invention.

Fig. 6 is a sectional view schematically showing a configuration of one aspect of the scintillator panel of the present invention.

FIG. 7 is a cross-sectional view schematically showing a configuration of a radiographic image detection apparatus including one aspect of the scintillator panel of the present invention having a partition wall.

Fig. 8 is a perspective view schematically showing a configuration of the scintillator panel of the present invention having a partition wall.

Fig. 9 is a sectional view schematically showing a partition wall, a buffer layer, and a substrate in one aspect of the scintillator panel of the present invention having a partition wall.

Fig. 10 is a cross-sectional view schematically showing a configuration of one aspect of the scintillator panel of the present invention having a partition wall.

The scintillator panel of the present invention is characterized by comprising a substrate and a phosphor layer containing a phosphor powder. The surface of the phosphor layer has a plurality of depressions, and the area A of the depression opening is 500 to 70,000 μm ² . The ratio D / T of the thickness T of the bulk layer to the depth D of the depression is 0.1 to 0.9.

The specific structure of the scintillator panel of the present invention is described below using drawings, but the present invention is not limited by these.

FIG. 1, FIG. 3 to FIG. 5 and FIG. 7 are cross-sectional views schematically showing the configuration of a radiation image detection device including a scintillator panel of the present invention. Figures 2 and 8 are perspective views schematically showing the structure of the scintillator panel of the present invention. The radiological image detection device 1 includes a scintillator panel 2, a detection substrate 3, and a power supply unit 13.

The scintillator panel 2 includes a substrate 4 and a phosphor layer 7 formed on the substrate 4 and containing a phosphor powder. The surface of the phosphor layer 7 has a plurality of depressions.

The detection substrate 3 is provided on the substrate 12 with a photoelectric conversion layer 10 and an output layer 11 in which pixels composed of photoelectric conversion elements and TFTs are formed in two dimensions. The light-emitting surface of the scintillator panel 2 and the photoelectric conversion layer 10 of the detection substrate 3 are passed through the adhesive layer 9 and then adhered or brought into close contact to form a radiation image detection device 1. At this time, the pixels of the photoelectric conversion element correspond to one or more depressions on the surface of the phosphor layer. One pixel can correspond to one depression, or one pixel can correspond to more than two depressions. The number of depressions of the phosphor layer corresponding to one pixel of the photoelectric conversion element should be equal.

The radiation incident on the radiation image detection device 1 is absorbed by the phosphor contained in the phosphor layer 7 and emits visible light. Hereinafter, the light emitted from the phosphor is referred to as "luminous light from the phosphor". The light emitted from the phosphor reaching the photoelectric conversion layer 10 undergoes photoelectric conversion in the photoelectric conversion layer 10, passes through the output layer 11, and is output in the form of an electronic signal. Out.

The substrate material of the scintillator panel includes, for example, glass, ceramics, semiconductors, polymer compounds, or metals having radiation permeability. Examples of the glass include quartz, borosilicate glass, and chemically strengthened glass. Examples of the ceramic include sapphire, silicon nitride, and silicon carbide. Examples of the semiconductor include silicon, germanium, gallium arsenide, gallium phosphide, or gallium nitride. Examples of the polymer compound include cellulose acetate, polyester, polyamide, polyimide, triacetate, polycarbonate, and carbon fiber reinforced resin. Examples of the metal include aluminum, iron, copper, and metal oxides.

In addition, from the standpoint of ease of transport of the scintillator panel and lighter development of the scintillator panel, the thickness of the substrate is preferably 2.0 mm or less, and more preferably 1.0 mm or less. In addition, in order to efficiently use the light emitted from the phosphor, a substrate having a high reflectance is preferred. Examples of suitable materials for the substrate include glass and polymer compounds. A particularly suitable example is a highly reflective polyester substrate. From the viewpoint of high radiation permeability and low specific gravity, a highly reflective polyester substrate is preferably a white polyester substrate containing pores.

A phosphor layer is formed on the substrate. The phosphor layer contains phosphor powder. Here, the phosphor powder refers to a phosphor having an average particle diameter D50 of 40 μm or less. Examples of the phosphor include CsI, CsBr, Gd ₂ O ₂ S (hereinafter referred to as “GOS”), Gd ₂ SiO ₅ , BiGe ₃ O ₁₂ , CaWO ₄ , Lu ₂ O ₂ S, Y ₂ O ₂ S, LaCl _{3, LaBr 3, LaI 3,} CeBr 3, CeI 3 or LuSiO _5. In order to improve luminous efficiency, an activator may be added to the phosphor. Examples of the activator include sodium (Na), indium (In), scandium (Tl), lithium (Li), potassium (K), scandium (Rb), sodium (Na), scandium (Tb), cerium (Ce), Europium (Eu) or Europium (Pr), and for the sake of high chemical stability and high luminous efficiency, Tb-activated GOS (GOS: Tb) formed by adding Tb to GOS is preferred.

The phosphor powder is preferably spherical, flat, or rod-shaped. The average particle diameter D50 of the phosphor is preferably 0.1 to 40 μm, preferably 1.0 to 25 μm, and more preferably 1.0 to 20 μm. On the other hand, if D50 is less than 0.1 μm, there may be cases where sufficient light emission cannot be obtained due to surface defects of the phosphor. In addition, if D50 exceeds 40 μm, the detection intensity of each photoelectric conversion element may fluctuate greatly, and a clear image may not be obtained.

The average particle diameter D50 of the phosphor powder can be measured by using a particle size distribution measuring device (for example, MT3300; manufactured by Nikkiso Co., Ltd.). The phosphor powder is added to a water-filled sample chamber and subjected to ultrasonic treatment for 300 seconds. Measurements were made thereafter.

The surface of the phosphor layer has a plurality of depressions. Here, the surface of the phosphor layer refers to the side of the phosphor layer that is located on the opposite side of the substrate. With the depressions in the phosphor layer, the luminous rays of the phosphor can be condensed here, and the scattering of the luminous rays is suppressed, so that a sharper image can be obtained. In addition, by providing the phosphor layer with depressions, it is possible to reduce light absorption caused by the phosphor before reaching the photoelectric conversion layer, and to efficiently use the emitted light.

Examples of the shape of the depression included in the phosphor layer include the shapes shown in FIG. 1 or FIGS. 3 to 5.

The area A of the recessed opening of the phosphor layer must be 500 to 70,000 μm ² . If the area A is less than 500 μm ² , the light emitted from the phosphor cannot be focused in the depression, and the scattering of the light emitted cannot be suppressed. On the other hand, if the area A exceeds 70,000 μm ² , since the depression is larger than the pixel size of the photoelectric conversion element, the detected light amount of each pixel is variated, so that a clear image cannot be obtained.

The area A can be obtained by analyzing an image obtained by scanning a phosphor layer in a direction perpendicular to the substrate at a magnification of 20 times using a laser microscope (for example, VK-9500; manufactured by Keyence Corporation). More specifically, five depressions can be randomly selected from the scanned image, and the length required to obtain the area mathematically according to the shape of each opening can be measured (for example, if the shape of the opening is a perfect circle, then Its diameter; if the shape of the opening is a square, its side length), the area of each opening is obtained, and then the average of the five is obtained.

Fig. 6 is a cross-sectional view schematically showing one aspect of the scintillator panel of the present invention. In the scintillator panel 2, a phosphor layer 7 having a thickness T is formed on the substrate 4. The surface of the phosphor layer 7 has a plurality of depressions. The maximum width of the recessed opening is W, and the depth is D. In addition, the interval between adjacent recesses is defined as a pitch P. The distance between adjacent depressions here means the distance from the center point of the opening of a depression to the center point of the adjacent depression.

The maximum width W of the recess opening is preferably 30 to 300 μm, more preferably 40 to 250 μm, and even more preferably 40 to 150 μm. If the maximum width W of the opening is less than 30 μm, the luminous rays of the phosphor cannot be collected in the depression, and scattering of the luminous rays cannot be suppressed to obtain a sharp image. On the other hand, if the maximum width W of the opening exceeds 300 μm, the amount of light detected by the pixels of each photoelectric conversion element varies, so that a clear image may not be obtained.

Maximum width W of recessed opening, laser microscopy can be used A mirror (for example, VK-9500; manufactured by Keyence Co., Ltd.) is obtained by analyzing an image obtained by scanning a phosphor layer in a direction perpendicular to the substrate at a magnification of 20 times. More specifically, by randomly selecting 5 depressions in the scanned image, the length required mathematically according to the shape of each opening portion can be calculated (for example, if the shape of the opening portion is a perfect circle, it is Diameter; if the shape of the opening is a square, its diagonal length) is obtained by averaging five.

The thickness T of the phosphor layer is preferably 120 to 1000 μm, more preferably 120 to 500 μm, and even more preferably 120 to 350 μm. If the thickness T of the phosphor layer is less than 120 μm, the radiation may not be sufficiently converted into visible light, and a sufficient amount of luminous light may not be obtained. On the other hand, if the thickness T of the phosphor exceeds 1000 μm, a high-intensity light-emitting ray generated by a phosphor that is irradiated with radiation first and exists on the side of the radiation direction cannot reach the photoelectric conversion layer and cannot be high. A case where light is efficiently used. Even a large amount of phosphor powder must be used, which increases the cost of the scintillator panel.

The thickness T of the phosphor layer can be measured by the following method. First, positions where the phosphor layer is not recessed are randomly selected and cut in a direction perpendicular to the substrate. An optical microscope (for example, OPTISHOT; manufactured by Nikon Co., Ltd.) was used to observe the cross section at a magnification of 20 times, and randomly selected five measurement positions among the obtained images to measure the phosphor layer height at each measurement position. This operation was repeated 5 times, and the average value of all the obtained height values (5 × 5) was determined as the thickness T of the phosphor layer.

Depression depth D of the phosphor layer can be 20 times magnification using a laser microscope (eg, VK-9500; manufactured by Keyence Co., Ltd.) An image obtained by scanning the phosphor layer in a direction perpendicular to the substrate is analyzed and obtained. More specifically, in the scanned image, five depressions are randomly selected, and the average value of the distance from each opening to the deepest portion in a direction perpendicular to the substrate is calculated to obtain the depth D of the depression.

The ratio D / T of the thickness T of the phosphor layer to the depth D of the phosphor layer must be 0.1-0.9, and preferably 0.2-0.8. If D / T is less than 0.1, the radiation cannot be sufficiently converted into visible light, and a sufficient amount of luminous light cannot be obtained. In addition, the luminous light emitted from the phosphor collected in the recess will leak light on the substrate side, and cannot reach the photoelectric conversion layer, and the utilization efficiency of the luminous light is reduced. On the other hand, if D / T exceeds 0.9, the luminous rays of the phosphor cannot be condensed in the depression, and the scattering of the luminous rays cannot be suppressed to obtain a sharp image.

The phosphor layer is preferably one having 500 to 50000 depressions / cm ² on the surface, and more preferably having 1,200 to 15,000 depressions / cm ² on the surface. If the number of depressions is less than 500 / cm ² , there may be a large variation in the number of depressions of the phosphor layer corresponding to one pixel of the photoelectric conversion element, and a clear image may not be obtained. On the other hand, if the number of depressions exceeds 50,000 pieces / cm ² , the luminous rays of the phosphor cannot be focused at the depressions, and even the amount of the phosphor powder is reduced, so that the luminous rays with sufficient intensity may not be obtained. Situation.

The number of depressions in the phosphor layer can be analyzed by using an optical microscope (for example, OPTISHOT; manufactured by Nikon Co., Ltd.) to analyze an image obtained by scanning the phosphor layer in a direction perpendicular to the substrate at a magnification of 20 times. Find it. More specifically, it can be obtained by randomly selecting 10 areas of 1 mm ² in the scanned image, measuring the number of depressions, and converting the average value to a value per 1 cm ² .

The pitch P between adjacent recesses may be appropriately changed in accordance with the pitch of the corresponding photoelectric conversion element, and a range of 50 to 350 μm is preferable, and a range of 50 to 280 μm is more preferable. In addition, the distance P between adjacent recesses is preferably a certain value within the aforementioned range. That is, in order to make the number of depressions corresponding to each pixel of the photoelectric conversion element uniform, the depressions of the phosphor layer should be provided at regular intervals with a certain value in the range of 50 to 350 μm. If the pitch P is less than 50 μm, there is a case where the light emitted from the phosphor cannot be collected in the recess. On the other hand, if the pitch P exceeds 350 μm, it may be difficult to make the photoelectric conversion element correspond to one or more depressions per pixel. The pitch P is preferably a constant value in a range of 50 to 280 μm.

The distance P between the adjacent recesses can be obtained by analyzing the image obtained by scanning the phosphor layer in a direction perpendicular to the substrate at a magnification of 20 times using a laser microscope (for example, VK-9500; manufactured by Keyence Co., Ltd.). Got. More specifically, in the scanned image, the distances from the center point of the opening of the depression to the center point of the adjacent depression are randomly measured, and the average value is calculated as the pitch P of the depression.

The shape of the depression of the phosphor layer is preferably such that the area of the depression section parallel to the substrate is the largest at the opening, and even if the depression depth D becomes larger, the area in the horizontal direction does not change, or as the depth D becomes larger The shape in which the area in the horizontal direction becomes smaller. The shape of the depression in the phosphor layer is preferably a slightly conical shape with the opening as the bottom surface. Here the slightly conical "slightly", the shape of the depression does not necessarily mean a cone strictly, and the bottom surface (the shape of the opening of the depression) can also be elliptical or top. The dots (the shape of the deepest part of the depression) may also have rounded corners as shown in FIG. 2. By making the depression into such a shape, the luminous light collected at the depression will not be enclosed inside the depression, and the luminous light can be used efficiently.

A method of forming a phosphor layer on a substrate includes a method of applying a phosphor powder-containing paste, that is, a phosphor paste, on a substrate to form a coating film. By forming depressions in the coating film of the phosphor paste obtained in this way, a phosphor layer having a plurality of depressions on the surface can be obtained. The phosphor paste coating method for obtaining a coating film includes, for example, a screen printing method, a bar coater, a roll coater, a die coater, or a blade coater.

The phosphor paste may also contain an organic binder. Examples of the organic binder include polyvinyl butyral, polyvinyl acetate, polyvinyl alcohol, ethyl cellulose, methyl cellulose, polyethylene, polymethylsiloxane, and polymethylphenylsiloxane. Silicone resin, polystyrene, butadiene / styrene copolymer, polystyrene, polyvinylpyrrolidone, polyamide, high molecular weight polyether, copolymer of ethylene oxide and propylene oxide, polypropylene Amidine or acrylic resin.

The phosphor paste may contain an organic solvent. In the case where the phosphor paste contains an organic binder, the organic solvent should preferably be a good solvent and should have a strong hydrogen bond. Examples of such organic solvents include diethylene glycol monobutyl ether acetate, ethylene glycol monobutyl ether alcohol, diethylene glycol monobutyl ether, methyl ethyl ketone, cyclohexanone, isobutanol, and isopropyl alcohol. Alcohol, terpineol, benzyl alcohol, tetrahydrofuran, dimethylarylene, dihydroterpineol, γ-butyrolactone, dihydroterpine acetate, 3-methoxy-3-methyl-methylbutane Alcohol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, N, N-dimethylformamide, hexanediol Or bromobenzoate.

To adjust the viscosity, the phosphor paste may also contain a tackifier, a plasticizer, or an anti-settling agent.

Examples of a method for forming a depression in a coating film of a phosphor paste include an etching method, a mold rolling method, a sandblasting method, and a photosensitive paste method. In particular, a method for extruding a phosphor paste coating film by using a calender to form a metal mold having a convex pattern corresponding to the depression is performed because the number of steps is small and the selectivity of the phosphor paste material is high. It is suitable because impurities can be prevented from being mixed into the phosphor paste coating film. The material of the metal mold may be metal, ceramic, or resin, and preferably a transparent or white ceramic. In addition, since the convex pattern formed in the metal mold corresponds to the depression as described above, it must be formed in accordance with the target depression shape and pitch. Specifically, the convex pattern of the metal mold should be formed in accordance with the above-mentioned suitable depression shape and pitch.

Specifically, a metal mold for forming a convex pattern on a phosphor paste coating film is preferably rolled at 0.1 to 100 MPa, and more preferably rolled at 0.3 to 10 MPa. In addition, when a metal mold is used for the pressing delay, heating can be performed at 25 to 200 ° C. to appropriately form a depression in the phosphor paste coating film.

The scintillator panel preferably further has a partition wall that separates the phosphor layer into a plurality of cells.

FIG. 7 is a cross-sectional view schematically showing a configuration of a radiographic image detection apparatus including a scintillator panel having a partition shape. The scintillator panel 2 shown in FIG. 7 includes a substrate 4, a partition wall 6 placed on the substrate 4, and a phosphor layer 7 divided into a plurality of grooves by the partition wall 6. Phosphor layer 7 It also has multiple depressions.

A buffer layer 5 is preferably formed between the substrate 4 and the partition wall 6. By forming the buffer layer 5, the partition wall 6 can be formed stably. In addition, by increasing the reflectance of the buffer layer 5 with respect to visible light, the light emitted by the phosphor powder contained in the phosphor layer 7 can efficiently reach the photoelectric conversion layer 10 on the detection substrate 3.

In addition, by forming a reflective layer 8 having a high reflectivity in each of the grooves partitioned by the partition wall 6, the light emitting light of the phosphor powder contained in the phosphor layer 7 can efficiently reach the photoelectric conversion layer of the detection substrate 3. 10.

Since the phosphor layer is partitioned by the partition wall, the size and pitch of the pixels separated by the partition wall of the scintillator panel 2 by the size and pitch of the pixels of the photoelectric conversion elements arranged in a grid pattern on the detection substrate 3 and The photoelectric conversion elements of the photoelectric conversion layer 10 are arranged in a manner corresponding to the pitch, which can prevent scattering of light emitted by the phosphor from affecting the adjacent grooves.

The height h of the partition wall is preferably 120 to 1000 μm, and more preferably 160 to 500 μm. When the height h exceeds 1000 μm, it may be difficult to form a partition wall. On the other hand, if the height h is less than 120 μm, the amount of phosphor powder is reduced, so that there may be cases where a sufficient amount of luminescent light cannot be obtained.

The shape of the partition wall may be appropriately selected in accordance with the shape of the pixels of the photoelectric conversion element included in the detection substrate, and a grid shape as shown in FIG. 8 is preferable. Examples of the shape of the openings of the grooves divided into a grid include, for example, squares, rectangles, parallelograms, or trapezoids. From the viewpoint of relatively uniform light intensity, squares are preferred.

The distance between adjacent partitions in a grid-like partition, That is, the distance P ′ is preferably 50 to 1000 μm. If the pitch P ′ is less than 50 μm, it may be difficult to form a partition wall. On the other hand, if the pitch P ′ exceeds 1000 μm, a sharp image may not be obtained.

The width Wb of the bottom of the partition wall should be 15 ~ 150 μm. The width Wm of the 50% height of the partition wall should be 15 ~ 120μm. The width Ws at the 75% height of the partition wall and the width Wt at the top of the partition wall should be 80 μm or less. If the width Wb and the width Wm are less than 15 μm, the partition wall is easily damaged. On the other hand, if the width Wb exceeds 150 μm or the width Wm exceeds 120 μm, the amount of phosphor powder decreases, and therefore, there may be cases where sufficient intensity of light emission cannot be obtained. If the widths Ws and Wt exceed 80 μm, the progress of the light emitted by the phosphor may be blocked, the light may not reach the photoelectric conversion layer, and the use efficiency of the light emitted may be reduced. In addition, as shown in FIG. 9, the width Wb refers to the width of the partition wall where the partition wall meets the substrate or the buffer layer when the partition wall is cut vertically along the height direction and the long side direction. Here, the grid-like partition wall is cut at a half position of the pitch P '. In addition, the width Wm refers to the width of the partition wall where the height in the same section is 50% of the height h of the partition wall. The width Ws refers to the width of the partition wall where the height on the same section is 75% of the height h of the partition wall. The width Wt refers to the width of the partition wall where the height on the same section is 90% of the height h of the partition wall. The height h, the width Wb, the width Wm, the width Ws, and the width Wt can be obtained by observing the cross section of the partition wall by SEM, measuring three or more points, and calculating the average of these. In addition, in order for the light emitted by the phosphor to reach the photoelectric conversion layer efficiently, the cross-section of the partition wall should be a shape in which the width of the partition wall decreases from the bottom to the top, that is, as shown in FIGS. 7 and 9 Cone.

The material of the partition wall includes, for example, acrylic resin, Resin, glass, or metal such as ester resin or epoxy resin. From the viewpoint of productivity and mechanical strength, glass is preferred as the main component. Here, glass is used as the main component, which means that the proportion of glass in the partition wall is 60% by mass or more. This ratio is preferably 70% by mass or more.

Examples of a method for forming the partition wall include an etching method, a screen printing method, a sandblasting method, a metal mold transfer method, and a photosensitive paste method. In order to obtain a high-definition partition wall, a photosensitive paste method is preferably used.

The photosensitive paste method refers to a method of forming a partition wall having the following steps: a coating step of applying a photosensitive paste containing a photosensitive organic component on a substrate to form a photosensitive paste coating film; and having a desired opening through An exposure step of exposing the obtained photosensitive paste coating film to an exposure mask; an imaging step of dissolving and removing a portion of the photosensitive paste coating film that is soluble in a developing solution after exposure.

In addition, the photosensitive paste may further include a low melting point glass powder in the photosensitive paste, heat the photosensitive paste pattern after the developing step to a high temperature, decompose and distill off organic components, and soften and sinter the low melting point glass. The firing step to form the partition wall.

The heating temperature in the firing step is preferably 500 to 700 ° C, and more preferably 500 to 650 ° C. If the heating temperature is above 500 ° C, the organic components will be completely decomposed and distilled off, and the low-melting glass powder will be softened and sintered. On the other hand, if the heating temperature exceeds 700 ° C, the substrate or the like may be severely deformed.

It is preferable that the photosensitive paste contains an organic component and an inorganic powder. The proportion of the inorganic powder in the photosensitive paste is preferably 30 to 80% by mass, and more preferably 40 to 70% by mass. If the proportion of inorganic powder is not full 30% by mass, that is, if there are too many organic components, the shrinkage rate in the firing step becomes large, and the partition wall is easily damaged. On the other hand, if the content of the inorganic powder exceeds 80% by mass, that is, if there are too few organic components, the stability or coatability of the photosensitive paste will be adversely affected. In addition, the dispersibility of the inorganic powder will decrease and the partition wall will be easily broken. . In addition, the proportion of the low-melting glass powder in the inorganic powder is preferably 50 to 100% by mass. If the proportion of the low-melting glass powder is less than 50% by mass, sintering may be insufficient and the strength of the partition wall may be reduced.

The softening temperature of the low melting glass powder is preferably 480 ° C or higher. If the softening temperature is less than 480 ° C, the organic component may remain in the glass without being decomposed and distilled off, which may cause coloring and the like. If the heating temperature in the firing step is taken into consideration, the softening temperature of the low melting glass is preferably 480 to 700 ° C, more preferably 480 to 640 ° C, and even more preferably 480 to 620 ° C.

The softening temperature of the low melting point glass can be measured using a differential thermal analysis device (for example, a differential type differential thermal balance TG8120; manufactured by Rigaku Co., Ltd.). From the obtained DTA curve, the tangent method is used to calculate the endothermic peak by extrapolation. Endothermic temperature. More specifically, alumina powder was used as a standard sample, a differential thermal analysis device was heated from room temperature to 20 ° C./minute, and a low-melting glass powder was measured as a sample to obtain a DTA curve. From the obtained DTA curve, the endothermic end temperature of the endothermic peak can be obtained by extrapolation of the tangent method, and the obtained softening point Ts can be determined as the softening temperature of the low melting point glass.

The coefficient of thermal expansion of low melting glass is preferably 40 to 90 × 10 ^-7 (/ K). If the thermal expansion coefficient exceeds 90 × 10 ^-7 (/ K), the obtained scintillator panel may become warped, and crosstalk of luminous rays may reduce the sharpness of the image. On the other hand, if the thermal expansion coefficient is less than 40 × 10 ^-7 (/ K), the softening temperature of the low-melting glass may not be sufficiently low.

Examples of the component contained to lower the melting point of the glass include lead oxide, bismuth oxide, zinc oxide, and an alkali metal oxide. The softening temperature of the low-melting glass should be adjusted according to the content ratio of the alkali metal oxide selected from the group consisting of lithium oxide, sodium oxide, and potassium oxide.

The proportion of the alkali metal oxide in the low-melting glass should preferably be 2 to 20% by mass. If the ratio of the alkali metal oxide is less than 2% by mass, the softening temperature of the low-melting glass becomes high, and it is necessary to heat it at a high temperature when the firing step is performed, the substrate is easily distorted, or the partition wall is easily damaged. On the other hand, when the proportion of the alkali metal oxide exceeds 20% by mass, the viscosity of the low-melting glass is excessively reduced during the firing step, and the shape of the obtained partition wall is liable to be distorted. In addition, the porosity of the obtained partition wall became too small, and the obtained scintillator panel could not obtain sufficient intensity of light emission.

In addition to the low-melting glass containing alkali metal oxides, in order to adjust the viscosity at high temperatures, it is preferable to contain zinc oxide in an amount of 3 to 10% by mass. If the proportion of zinc oxide is less than 3% by mass, the viscosity of the low-melting glass is too high at high temperatures. On the other hand, when the proportion of zinc oxide exceeds 10% by mass, the cost of the low-melting glass increases.

In addition, in addition to the above-mentioned alkali metal oxides and zinc oxide, low-melting glass can also be used to adjust the stability and crystallinity of low-melting glass by containing silicon oxide, boron oxide, aluminum oxide, and alkaline earth metal oxides. , Transparency, refractive index and thermal expansion characteristics. Alkaline earth metal oxides should preferably be selected from the group consisting of magnesium, calcium, barium and strontium Of oxide.

An example of a suitable composition of a low-melting glass is disclosed below.

Alkali metal oxide: 2-20% by mass

Zinc oxide: 3 ~ 10% by mass

Silicon oxide: 20 ~ 40% by mass

Boron oxide: 25 ~ 40% by mass

Alumina: 10-30% by mass

Alkaline earth metal oxide: 5-15% by mass.

The average particle diameter D50 of the low melting glass powder is preferably 1.0 to 4.0 μm. If the average particle diameter D50 is less than 1.0 μm, the low-melting glass powder may be aggregated, the dispersibility may be reduced, and the coating property of the paste may be adversely affected. On the other hand, when the average particle diameter D50 exceeds 4.0 μm, the unevenness on the surface of the partition wall becomes large, and it is easy to cause damage.

For inorganic powders such as low-melting glass powders, the average particle diameter D50 can be measured using a particle size distribution measuring device (for example, MT3300; manufactured by Nikkiso Co., Ltd.). Inorganic powder is added to a sample chamber filled with water to perform ultrasonic waves. Measurements were made after 300 seconds of treatment.

In the firing step, in order to control the shrinkage rate or maintain the shape of the partition wall, the inorganic powder of the photosensitive paste may further contain a filler. The filler here refers to an inorganic powder that does not soften at 700 ° C. The filler is preferably high-melting glass or ceramic particles such as silica, alumina, titania or zirconia. However, in order to prevent the sintering of the low melting glass from being hindered, the proportion of the filler in the inorganic powder is preferably less than 50% by mass. In addition, the average particle diameter D50 of the filler is preferably 0.1 to 4.0 μm.

Examples of the photosensitive organic component contained in the photosensitive paste include a photosensitive monomer, a photosensitive oligomer, a photosensitive polymer, and a photopolymerization initiator. The photosensitive monomers, photosensitive oligomers, and photosensitive polymers herein refer to monomers having active carbon-carbon double bonds, which undergo photo-crosslinking or photo-polymerization upon irradiation with active light, etc., to change chemical structures Polymers, oligomers and polymers.

Examples of the photosensitive monomer include a compound having a vinyl group, an acrylic fluorenyl group, a methacryl fluorenyl group, or an acryl amine group, and a polyfunctional acrylate compound or a polyfunctional methacrylate compound is preferred. In order to increase the crosslinking density, the proportion of the polyfunctional acrylate compound and the polyfunctional methacrylate compound in the organic component is preferably 10 to 80% by mass.

Examples of the photosensitive oligomer and photosensitive polymer include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetate, and anhydrides thereof. A copolymer having a carboxyl group, which is copolymerized with a monomer such as methacrylate, acrylate, styrene, acrylonitrile, vinyl acetate, or 2-hydroxyacrylate. Examples of the method for introducing an active carbon-carbon double bond into an oligomer or polymer include, for example, a mercapto group, an amine group, a hydroxyl group, or a carboxyl group in an oligomer or a polymer, and a vinyl group having a glycidyl group or an isocyanate group. A method of reacting an unsaturated compound, phosphonium acrylate, chloromethacrylate, or allyl chloride, or a carboxylic acid such as maleic acid.

In addition, when a monomer or oligomer having a urethane structure is used, when the firing step is performed, stress relaxation occurs after heating starts, and a photosensitive paste having a pattern that is not easily broken can be obtained.

Photopolymerization initiator refers to the product produced by the irradiation of active light. Free radical generating compounds. Examples of the photopolymerization initiator include benzophenone, o-benzylidene benzoate, 4,4-bis (dimethylamino) benzophenone, and 4,4-bis (diethylamino) ) Benzophenone, 4,4-dichlorobenzophenone, 4-benzyl-4-methylbenzophenone, dibenzyl ketone, fluorenone, 2,2-dimethoxy-2-benzene Acetophenone, 2-hydroxy-2-methylphenylacetone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone , Diphenylethylenedione, benzylmethoxyethylacetal, benzoin, benzoin methyl ether, benzoin butyl ether, anthraquinone, 2-tert-butylanthraquinone, anthrone, benzoanthrone, diphenyl Acylcycloheptanone, methylene anthrone, 4-azidobenzylidene acetophenone, 2,6-bis (p-azidobenzylidene) cyclohexanone, 2,6-bis (p-azidobenzylidene) ) -4-methylcyclohexanone, 1-phenyl-1,2-butanedione-2- (O-methoxycarbonyl) oxime, 1-phenyl-1,2-propanedione-2 -(O-ethoxycarbonyl) oxime, 1,3-diphenylglycerone-2- (O-ethoxycarbonyl) oxime, 1-phenyl-3-ethoxyglycerone-2- (O-benzylidene) oxime, Michelin, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinyl-1-acetone, 2-benzyl- 2-dimethyl Amino-1- (4-morpholinylphenyl) butanone-1, naphthalenesulfonyl chloride, quinolinsulfonyl chloride, N-phenylthioacridone, benzothiazole disulfide, triphenylphosphine A combination of a photoreducible pigment such as benzamidine peroxide, eosin, or methylene blue, and a reducing agent such as ascorbic acid or triethanolamine.

When the photosensitive linear paste contains a copolymer having a carboxyl group, the solubility in an alkaline aqueous solution can be improved. The acid value of the copolymer having a carboxyl group is preferably 50 to 150 mgKOH / g. When the acid value is 150 mgKOH / g or less, the development allowable amount becomes large. On the other hand, if the acid value is 50 mgKOH / g or more, the solubility of the unexposed portion in the developing solution will not decrease, and a thin-line partition wall pattern can be obtained by using a low-concentration developing solution. Carboxyl The copolymer preferably has an ethylenically unsaturated group in a side chain. Examples of the ethylenically unsaturated group include acrylfluorenyl, methacrylfluorenyl, vinyl, and allyl.

The relationship between the average refractive index n1 of the low-melting glass powder contained in the photosensitive paste and the average refractive index n2 of the photosensitive organic component satisfies the relationship of -0.1 ≦ n1-n2 ≦ 0.1, and satisfies −0.01 ≦ n1-n2 ≦ 0.01 The relationship is preferably to satisfy the relationship of -0.005 ≦ n1-n2 ≦ 0.005. By satisfying these conditions, during the exposure step, light scattering is suppressed at the interface between the low-melting glass powder and the photosensitive organic component, and a finer pattern can be formed.

The average refractive index n1 of the low-melting glass powder can be measured by a Beck line detection method. More specifically, the refractive index can be measured five times at 25 ° C. at a wavelength of 436 nm (g-ray), and the average value can be determined as n1. The average refractive index n2 of the photosensitive organic component can be determined by measuring the coating film formed of only the photosensitive organic component with an ellipsometer. More specifically, the refractive index can be measured five times at 25 ° C. at a wavelength of 436 nm (g-ray), and the average value can be determined as n 2.

A method for producing the photosensitive paste includes, for example, a method of adding an organic solvent to the inorganic powder and the photosensitive organic component as necessary, and uniformly mixing and dispersing the mixture with a three-roller or kneader.

The viscosity of the photosensitive paste can be appropriately adjusted by adding, for example, an inorganic powder, a thickener, an organic solvent, a polymerization inhibitor, a plasticizer, or an anti-settling agent. The viscosity of the photosensitive paste should be 2 ~ 200Pa. s. When the photosensitive paste is applied by a spin coating method, it is preferably 2 to 5 Pa. s, film thickness is 10 ~ 40μm after coating by screen printing method once In the case of the coating film, it should be 50 ~ 200Pa. s.

An example of a method for producing a partition wall using a photosensitive paste is disclosed below. A photosensitive paste is applied to the entire surface or a part of the substrate to form a photosensitive paste coating film. The coating method includes, for example, a spin coating method, a screen printing method, or a method using a bar coater, a roll coater, a die coater, or a blade coater. The thickness of the photosensitive paste coating film can be appropriately adjusted by, for example, the number of application times, the mesh size of the screen, or the viscosity of the photosensitive paste.

The exposure of the obtained photosensitive paste coating film is generally performed by exposing through a photomask, and exposure can also be performed by drawing directly with laser light or the like. Examples of the exposure light include near-infrared rays, visible light rays, and ultraviolet rays, and ultraviolet rays are preferred. The ultraviolet light source may be, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a halogen lamp, or a germicidal lamp, and is preferably an ultra-high-pressure mercury lamp. Examples of the exposure conditions include an ultrahigh-pressure mercury lamp with an output of 1 to 100 mW / cm ² , and exposure for 0.01 to 30 minutes.

The unexposed portion is dissolved and removed by utilizing the difference in solubility between the exposed portion and the unexposed portion of the photosensitive paste coating film after exposure to the developing solution, and the partition wall pattern can be obtained by washing (washing) and drying as necessary. Examples of the development method include a dipping method, a spray method, a brushing method, and an ultrasonic method. When the partition wall height h exceeds 300 μm, the spray method or the ultrasonic method is preferred.

The ultrasonic method refers to a method in which an unexposed portion is dissolved and removed by ultrasonic waves. Not only the unexposed part, but also the semi-hardened part with insufficient hardening in the exposed part will also be attacked by the developing solution to cause a dissolution reaction, so a partition wall pattern with a thinner line width can be formed. In addition, washing (washing) after development Ultrasound can also be used.

In order to make the developing solution corrode the unexposed part and the exposed part to an appropriate degree, when performing the ultrasonic method, the ultrasonic frequency should be 20 to 50 kHz. The ultrasonic intensity (power density) of the substrate per unit area should be 40 to 100 W / cm ² . The ultrasonic irradiation time is preferably 20 to 600 seconds, more preferably 30 to 500 seconds, and more preferably 60 to 300 seconds.

When the photosensitive paste contains a compound having an acidic group such as a copolymer having a carboxyl group, an alkali aqueous solution can be used as a developing solution. Examples of the alkaline aqueous solution include an aqueous solution of an inorganic base such as sodium hydroxide, sodium carbonate, or calcium hydroxide, or an aqueous solution of an organic base such as tetramethylammonium hydroxide, trimethylbenzyl ammonium hydroxide, monoethanolamine, or diethanolamine. . From the viewpoint of being easily decomposed and distilled off in the firing step, an organic alkali aqueous solution is preferred. In order to dissolve the unexposed portion and the exposed portion to an appropriate degree, the concentration of the organic alkali aqueous solution is preferably 0.05 to 5% by mass, and more preferably 0.1 to 1% by mass. From the standpoint of step control, the temperature during development is preferably 20 to 50 ° C.

When the firing step is suitable, the pattern of the partition wall obtained as described above is fired in a firing furnace under a gas environment such as air, nitrogen, or hydrogen. Examples of the firing furnace include a batch-type firing furnace and a belt-type continuous firing furnace.

When the pattern of the partition wall containing the low melting point glass is fired, the inorganic powder containing the low melting point glass is softened and sintered during the firing step, and is fused to each other, but there may be voids remaining in between. The existence ratio of the void contained in the partition wall can be adjusted by the heating temperature in the firing step. In order to balance the reflection of the luminous effect of the phosphor with the effect of the partition wall Strength, the proportion of voids in the entire partition wall, that is, the porosity, is preferably 2-25% by volume, more preferably 5-25% by volume, and even more preferably 5-20% by volume. If the porosity is less than 2%, the reflectance of the partition wall may be lowered, and the light emission amount of the scintillator panel may be reduced. On the other hand, if the porosity exceeds 25%, the strength of the partition wall may be insufficient.

The porosity can be measured by precisely grinding the cross section of the partition wall and then observing it with an electron microscope. More specifically, the part generated by the void and the inorganic powder other than the void is converted into a 2-tone image, and the proportion of the void area in the cross-section of the partition wall is determined as the void ratio.

In order to relieve the stress during the firing step, a buffer layer should be formed between the partition wall and the substrate. In order to improve the reflectivity of the buffer layer, the material of the buffer layer should be low melting glass or ceramic. Examples of the low-melting glass include the same glass as that contained in the photosensitive paste used to form the partition wall. Examples of the ceramic include titanium oxide, aluminum oxide, and zirconia. In addition, in order to prevent the light emitted by the phosphor from passing through the buffer layer, the reflectance of the buffer layer for light having a wavelength of 550 nm should be 60% or more.

The buffer layer can be formed by dispersing an organic component and an inorganic powder such as a low-melting glass powder or a ceramic powder in a solvent, applying the obtained paste to a substrate and drying it to form a coating film, and then firing. The firing temperature is preferably 500 to 700 ° C, and more preferably 500 to 650 ° C.

The scintillator panel should have a concave reflective layer between the phosphor layer and the partition wall. The concave shape here refers to a state where the upper surface of the reflective layer in each groove, that is, the surface on the opposite side to the substrate, is recessed toward the substrate side. By forming a concave reflective layer in each groove separated by the partition wall, the luminous light of the fluorescent body can be reflected, and the leakage of the luminous light on the side of the partition wall can be reduced. Light.

The reflective layer can be made of a material that can transmit radiation and can reflect visible light with a wavelength of 300 to 800 nm from the phosphor. For the sake of less deterioration, metals such as silver, gold, aluminum, nickel, or titanium, or ceramics such as titanium oxide, zirconia, alumina, or zinc oxide are suitable.

The thickness of the concave reflective layer is preferably 0.01 to 50 μm, and more preferably 0.1 to 20 μm. When the thickness of the reflective layer is 0.01 μm or more, the reflectance becomes high. On the other hand, when the thickness of the reflective layer exceeds 50 μm, the amount of phosphor powder is reduced, and thus the emitted light becomes weak.

The thickness of the concave reflective layer can be determined by measuring the thickness of the reflective layer cross section at three or more points with a cross section when the partition wall is cut in the height direction and perpendicular to the long side direction, and calculating the average of these. Here, the grid-like partition wall is cut at a half position of the pitch P '.

Examples of the method for forming the reflective film include a vacuum film forming method, a plating method, a paste coating method, and spraying using a sprayer.

Specific examples of the paste coating method include a method of filling and drying a reflective layer paste in a groove partitioned by a partition wall. The reflective layer paste includes titanium oxide, zirconia, alumina, or zinc oxide. White ceramic powder; binder resin such as ethyl cellulose resin or polyvinyl butyral resin; and organic solvents.

In the case where the scintillator panel has a partition wall, a phosphor paste is applied from the partition wall, and the phosphor paste is filled into a groove partitioned by the partition wall.

Examples of the method for filling the phosphor paste into each tank include: For example, a screen printing method, a bar coater, a roll coater, a die coater, or a knife coater. Filling the phosphor paste under vacuum or placing it under vacuum for a certain period of time after filling the phosphor paste can suppress the occurrence of pores in the phosphor layer that can cause image defects.

In this aspect, a method of forming depressions on the surface of the phosphor layer includes, for example, a method of filling a phosphor paste into a groove, and then drying the phosphor paste. In this case, the depression of the phosphor layer can be set to an arbitrary shape by controlling the viscosity of the phosphor paste, the solid content ratio of the phosphor paste, or the drying conditions. In this case, the viscosity of the phosphor paste should be 10 ~ 500Pa. s. The solid content ratio of the phosphor paste refers to the proportion of the components that cannot be distilled off by drying in the entire phosphor paste. The solid content ratio of the phosphor paste is preferably 5 to 95% by volume. Examples of the drying method include hot air drying and IR drying.

A cross-sectional view schematically showing one aspect of such a scintillator panel is shown in FIG. 10. The area A of the recessed opening portion of the phosphor layer can be determined as described above. In addition, the area of the opening portion where the height is 50% of the partition wall height h is set to Am, and the area of the opening portion where the height is 75% of the partition wall height h is set to As. Am and As can be measured by the same method as the opening area A.

In addition, as another method of forming a depression in the coating film of the phosphor paste, for example, a method of filling the groove with the phosphor paste, and then rolling the surface of the phosphor paste with protrusions.

In addition, when the scintillator panel has a partition wall, one recess or a plurality of recesses may be formed in each groove.

Regardless of whether or not there is a partition wall, the phosphor layer is preferably composed of a plurality of layers with different density of phosphor powder filling. The layer with the highest density of phosphor powder filling, that is, the high-density phosphor layer, has high reflectance. When the radiation irradiation direction is the substrate side, the high-fill-density phosphor layer is preferably located on the substrate side. In addition, by forming a concave high-fill-density phosphor layer in each groove separated by the partition wall, the luminous light of the phosphor can be reflected, and the luminous light can be prevented from leaking on the side of the partition wall. The filling density of the phosphor layer can be applied by applying a phosphor paste so that the thickness of the dried coating film becomes 300 μm, and drying it at 100 ° C. in an IR drying oven under normal pressure for 2 hours. The mass per unit volume of the formed phosphor paste coating film was calculated. The filling density of the high filling density phosphor layer is preferably 3.0 g / cm ³ or more, and more preferably 4.0 g / cm ³ or more.

The scintillator panel having the aforementioned recessed phosphor layer and the photoelectric conversion element disposed on the detection substrate face each other, and the scintillator panel and the detection substrate obtained in the manner described above are set, and the aforementioned A step of aligning the recess with the aforementioned photoelectric conversion element, and a step of bonding the scintillator panel and the detection substrate through an adhesive layer to obtain a radiation image detection device.

The method of aligning the recessed scintillator panel 2 with the detection substrate 3 forming the photoelectric conversion element is not particularly limited, and it is preferable to align the scintillator panel 2 with the highest brightness so that the image does not have moire.

An example of the alignment procedure of the scintillator panel 2 and the detection substrate 3 without a partition wall is listed below. On the scintillator panel 2 side, recesses having shapes different from those of the recesses provided in the pixel portion are formed at the four corners of the surface of the phosphor layer as alignment marks. Alignment mark here The shape of is not particularly limited, and when the shape of the depression is slightly conical, for example, it is preferably a cross shape. An alignment mark corresponding to the scintillator panel 2 side is formed on the detection substrate 3 side. By aligning the alignment mark of the scintillator panel 2 and the alignment mark of the detection substrate 3, the depression on the surface of the phosphor layer can be aligned with the photoelectric conversion element. The alignment mark should preferably be formed in a region outside the detection region of the photoelectric conversion layer.

An example of an alignment procedure of the scintillator panel 2 having a partition wall and the detection substrate 3 forming a photoelectric conversion element is listed below. On the side of the scintillator panel 2, auxiliary partition walls having shapes or sizes different from those of the partition walls are formed as alignment marks at the four corners of the area where the partition walls are formed. The shape of the auxiliary partition wall is not particularly limited, and when the shape of the partition wall is a lattice shape, it is preferably, for example, an oval shape. On the detection substrate 3 side, alignment marks corresponding to the scintillator panel 2 side are formed. By aligning the auxiliary partition wall of the scintillator panel 2 with the alignment mark of the detection substrate 3, the depression on the surface of the phosphor layer can be aligned with the photoelectric conversion element. The auxiliary partition wall should preferably be formed in an area further outside than the detection area of the photoelectric conversion layer.

After the alignment step, the scintillator panel and the detection substrate are adhered through an adhesive layer to obtain a radiation image detection device. By attaching an adhesive sheet or applying an adhesive, an adhesive layer can be formed on the detection substrate. The thickness of the adhesive layer should preferably be in the range of 0.5 to 30 μm. If the thickness of the adhesive layer is less than 0.5 μm, the adhesive force is low, which is not suitable. On the other hand, when the thickness of the adhesive layer is greater than 30 μm, when the light emitted from the phosphor layer passes through the adhesive layer, the light diffuses, and thus the sharpness of the image decreases.

The light emitted from the phosphor layer will pass through The photoelectric conversion element is detected, so the material of the adhesion layer should be a material with less absorption of light at the wavelength of light emitted by the phosphor. Specific examples of the adhesive layer are not particularly limited, and examples thereof include an adhesive sheet obtained by applying acrylic resin to both surfaces of a transparent polyester film.

[Example]

Examples and comparative examples are given below to further describe the present invention, but the present invention is not limited thereto.

(Production of photosensitive paste for partition walls)

To 38 parts by mass of an organic solvent were added 24 parts by mass of a photosensitive polymer, 6 parts by mass of a photosensitive monomer x, 4 parts by mass of a photosensitive monomer y, 6 parts by mass of a photopolymerization initiator, and 0.2 part by mass. Parts of a polymerization inhibitor and 12.8 parts by mass of an ultraviolet absorbent solution were dissolved by heating at 80 ° C. The obtained solution was cooled, and then 9 parts by mass of a viscosity modifier was added to obtain an organic solution for a partition wall.

Specific materials are described below.

Photosensitive polymer: obtained by subjecting a carboxyl group of a copolymer having a mass ratio of methacrylic acid / methacrylic acid / styrene to 40/40/30 to an addition reaction of 0.4 equivalent of glycidyl methacrylate Object (weight average molecular weight 43000; acid value 100)

Photosensitive monomer x: trimethylolpropane triacrylate

Photosensitive monomer y: tetrapropylene glycol dimethacrylate

Photopolymerization initiator: 2-benzyl-2-dimethylamino-1- (4-morpholinylphenyl) butanone-1 (IC369; manufactured by BASF)

Polymerization inhibitor: 1,6-hexanediol-bis [(3,5-di-third-butyl-4-hydroxyphenyl) propionate])

Ultraviolet absorbent solution: γ-butyrolactone 0.3% by mass solution (Sudan IV; manufactured by Tokyo Chemical Industry Co., Ltd.)

Organic solvent: γ-butyrolactone

Viscosity modifier: Flownon (registered trademark) EC121 (manufactured by Kyoeisha Chemical Co., Ltd.)

30 parts by mass of low-melting glass powder and 10 parts by mass of high-melting glass powder were added to 60 parts by mass of the organic solution for partition walls obtained in this way, and kneaded with a three-roll kneader to obtain the sensitivity for partition walls. Paste.

The specific composition is as follows.

Low melting point glass powder: SiO ₂ 27% by mass, B ₂ O ₃ 31% by mass, ZnO 6% by mass, Li ₂ O 7% by mass, MgO 2% by mass, CaO 2% by mass, BaO 2% by mass, Al ₂ O ₃ 23% by mass; softening temperature 588 ° C; thermal expansion coefficient 68 × 10 ^-7 (/ K); average particle diameter D50 is 2.3 μm

High melting point glass powder: SiO ₂ 30% by mass, B ₂ O ₃ 31% by mass, ZnO 6% by mass, MgO 2% by mass, CaO 2% by mass, BaO 2% by mass, Al ₂ O ₃ 27% by mass; softening temperature 790 ℃; coefficient of thermal expansion 32 × 10 ^-7 (/ K); average particle diameter D50 is 2.3 μm

(Production of paste for buffer layer)

To 95 parts by mass of the photosensitive paste for partition walls, 5 parts by mass of titanium oxide powder (average particle diameter D50 was 0.3 μm) was added and kneaded to obtain a paste for a buffer layer.

(Production of reflective layer paste A)

5 parts by mass of an organic binder (ethyl cellulose (100 cP)) was heated at 80 ° C. to dissolve it in 80 parts by mass of an organic solvent (terpineol), and 15 parts by mass of the obtained organic solution was added. Rutile titanium oxide ( The average particle diameter D50 was 0.25 μm) and kneaded to obtain a reflective layer paste A.

(Production of reflective layer paste B)

5 parts by mass of an organic binder (ethyl cellulose (100 cP)) was heated at 80 ° C to dissolve it in 60 parts by mass of an organic solvent (terpineol), and 35 parts by mass of the organic solution was added. Rutile titanium oxide (average particle diameter D50 is 0.25 μm) and kneaded to obtain a reflective layer paste B.

(Production of reflective layer paste C)

5 parts by mass of an organic binder (ethyl cellulose (14cP)) was heated at 80 ° C to dissolve it in 80 parts by mass of an organic solvent (terpineol), and 15 parts by mass of the organic solution was added Rutile titanium oxide (average particle diameter D50 is 0.25 μm) and kneaded to obtain a reflective layer paste C.

(Production of Fluorescent Paste A)

30 parts by mass of an organic binder (ethyl cellulose (7cp); specific gravity: 1.1 g / cm ³ ) was heated at 80 ° C. to dissolve it in 70 parts by mass of an organic solvent (terpineol, specific gravity: 0.93 g / cm ^3). ) To obtain an organic solution 1. In addition, Tb-activated Gd ₂ O ₂ S (Gd ₂ O ₂ S: Tb, specific gravity 7.3 g / cm ³ ) having an average particle diameter D50 of 10 μm was prepared as a phosphor powder.

85 parts by mass of phosphor powder was mixed with 15 parts by mass of the organic solution 1 to obtain a phosphor paste A. The filling density of the phosphor layer formed using the phosphor paste A was 4.0 g / cm ³ .

(Production of phosphor pastes B ~ H)

According to the composition shown in Table 1, the organic solutions 2 to 6 were produced by the same method as the production of the organic solution 1. Next, according to the composition shown in Table 2, the phosphor pastes B to H were produced by the same method as in the preparation of the phosphor paste A.

(Comparative example 1)

The above-mentioned phosphor paste A was coated on a 100 mm × 100 mm white PET film substrate (E6SQ; manufactured by Toray Co., Ltd.) with a die coater so that the thickness of the dried coating film was 300 μm. The IR drying oven was allowed to dry for 2 hours to form a phosphor paste coating film, that is, a full phosphor layer was coated to obtain a scintillator panel. Table 3 shows each parameter of the obtained scintillator panel.

The obtained scintillator panel was set on a detection substrate FPD (PaxScan3030; manufactured by Varian) to produce a radiographic image Detection device. Radiation with a tube voltage of 80 kVp was irradiated from the substrate side of the scintillator panel, and the luminous intensity of the scintillator panel was detected with PaxScan 3030. As a result, a sufficient luminous intensity was obtained. Hereinafter, the light emission intensity value of this Comparative Example 1 is set to 100, and a relative evaluation is performed. In addition, through a MTF chart made of lead, radiation of a tube voltage of 80 kVp was similarly irradiated from the substrate side of the scintillator panel, and data processing was performed on the obtained image to calculate the MTF of the image sharpness scale. In the following, the MTF value of this Comparative Example 1 is set to an image sharpness of 100, and a relative evaluation is performed.

(Example 1)

The above-mentioned phosphor paste A was coated on a 100 mm × 100 mm white PET film substrate (E6SQ; manufactured by Toray Co., Ltd.) with a die coater so that the thickness of the dried coating film became 300 μm at 100 ° C. An IR drying oven was allowed to dry for 2 hours to form a phosphor paste coating film, that is, a full phosphor layer was coated.

A plurality of convex patterns (a slightly conical shape with a radius of 50 μm and a height of 270 μm) are prepared in a two-dimensional matrix with a vertical and horizontal pitch of 194 μm, and a cross shape with a line width of 50 μm is formed at each of the four corners of the multiple convex patterns. A molding die made of patterned alumina (coefficient of thermal expansion 71 × 10 ^-7 (/ K)). The forming mold is pressed at a temperature of 80 ° C. on the phosphor layer formed as described above to form a recess on the surface of the phosphor layer, and a scintillator panel including a phosphor layer having a plurality of recesses on the surface can be obtained. Table 3 shows each parameter of the obtained scintillator panel.

The cross-shaped recesses of the obtained scintillator panel were aligned with the alignment marks of the FPD (PaxScan3030), and a radiation image detection device was manufactured. 80kVp tube voltage from the substrate side of the scintillator panel The light emission intensity of the scintillator panel was measured with PaxScan 3030. As a result, a high light emission intensity such as 102 was obtained compared to 100 in the light emission intensity of Comparative Example 1. In addition, through the MTF chart made of lead, the radiation of a tube voltage of 80 kVp was similarly irradiated from the substrate side of the scintillator panel, and the obtained image was subjected to data processing to calculate the MTF. 100, showing a higher value like 105.

(Example 2)

Except that the height of the convex pattern was changed to 240 μm, a scintillator panel was obtained by the same method as in Example 1, and the same evaluation as in Example 1 was performed. The parameters and evaluation results of the scintillator panel are shown in Table 3. The same applies to Examples 3 to 19 and Comparative Examples 2 to 4 below.

(Example 3)

Except that the height of the convex pattern was changed to 200 μm, a scintillator panel was obtained by the same method as in Example 1, and the same evaluation as in Example 1 was performed.

(Example 4)

A scintillator panel was obtained in the same manner as in Example 1 except that the height of the convex pattern was changed to 150 μm, and the same evaluation as in Example 1 was performed.

(Example 5)

Except that the height of the convex pattern was changed to 100 μm, a scintillator panel was obtained by the same method as in Example 1, and the same evaluation as in Example 1 was performed.

(Example 6)

A scintillator panel was obtained in the same manner as in Example 1 except that the height of the convex pattern was changed to 40 μm, and the same evaluation as in Example 1 was performed.

(Example 7)

A scintillator panel was obtained in the same manner as in Example 4 except that the radius of the convex pattern was changed to 15 μm, and the same evaluation as in Example 1 was performed.

(Example 8)

A scintillator panel was obtained in the same manner as in Example 4 except that the radius of the convex pattern was changed to 30 μm, and the same evaluation as in Example 1 was performed.

(Example 9)

Except that the radius of the convex pattern was changed to 70 μm, a scintillator panel was obtained by the same method as in Example 4, and the same evaluation as in Example 1 was performed.

(Example 10)

A scintillator panel was obtained by the same method as in Example 4 except that the radius of the convex pattern was changed to 90 μm, and the same evaluation as in Example 1 was performed.

(Example 11)

The scintillator panel was obtained by the same method as in Example 8 except that the pitch of the convex pattern was changed to 127 μm in both the vertical and horizontal pitches.

This scintillator panel was set on an FPD (PaxScan 2520; manufactured by Varian), and a radiological image detection device was produced, and the same evaluation as in Example 1 was performed.

(Example 12)

The scintillator panel was obtained by the same method as in Example 8 except that the pitch of the convex patterns was changed to 83 μm both in the vertical and horizontal pitches.

This scintillator panel was set on an FPD (PaxScan 3024; manufactured by Varian), and a radiological image detection device was produced, and the same evaluation as in Example 1 was performed.

(Example 13)

The thickness of the phosphor paste coating film was changed to 500 μm, the pitch of the convex pattern was changed to 42 μm in both the vertical and horizontal pitches, and the height of the convex pattern was changed to 200 μm. Except that, the same method as in Example 7 was used. A scintillator panel was obtained, and the same evaluation as in Example 12 was performed.

(Example 14)

The pitch of the convex pattern was changed to 582 μm in both the vertical and horizontal pitches, and the height of the convex pattern was changed to 100 μm. Except that the scintillator panel was obtained by the same method as in Example 9, the same procedure as in Example 1 was performed Evaluation. In addition, periodic noise was observed in the obtained image.

(Example 15)

The thickness of the phosphor paste coating film was changed to 150 μm, the radius of the convex pattern was changed to 30 μm, and the height of the convex pattern was changed to 30 μm. Except that the scintillator panel was obtained in the same manner as in Example 1. And the same evaluation as in Example 1 was performed.

(Example 16)

The thickness of the phosphor paste coating film was changed to 500 μm, the radius of the convex pattern was changed to 50 μm, and the height of the convex pattern was changed to 200 μm. Except that the scintillator panel was obtained in the same manner as in Example 1. , The same evaluation as in Example 1 was performed.

(Example 17)

The shape of the convex pattern was changed to a cylindrical shape having a vertical and horizontal pitch of 194 μm, a radius of 50 μm, and a height of 150 μm. A scintillator panel was obtained in the same manner as in Example 1 and evaluated in the same manner as in Example 1. .

(Example 18)

The shape of the convex pattern was changed to a regular quadrangular pillar having a vertical and horizontal pitch of 194 μm, a side length of 100 μm, and a height of 150 μm. A scintillator panel was obtained in the same manner as in Example 1 except that the same was performed as in Example 1. Evaluation.

(Example 19)

The shape of the convex pattern was changed to a regular quadrangular pyramid having a vertical and horizontal pitch of 194 μm, a side length of 100 μm, and a height of 150 μm. A scintillator panel was obtained in the same manner as in Example 1 except that the same was performed as in Example 1. Evaluation.

(Example 20)

The phosphor paste G was completely printed on a screen printing machine (manufactured by Microtek; the screen is # 350POL screen) so that the thickness of the dried coating film was 50 μm, and then the film was made in a 100 ° C. IR drying oven. After drying for 1 hour, the above-mentioned phosphor paste A was applied so that the total thickness of the phosphor paste coating film was 230 μm, and dried in an IR drying oven at 100 ° C. for 1 hour to form a difference in filling density. Multilayer structure phosphor coating film.

The surface of the coating film was shaped in the same manner as in Example 5. A scintillator panel having a recessed phosphor layer having a plurality of recessed surfaces was obtained, and the same evaluation as in Example 1 was performed.

(Example 21)

Apply the above-mentioned phosphor paste G with a die coater so that the thickness of the dried coating film becomes 50 μm, and then apply the above-mentioned phosphor paste A so that the total thickness of the phosphor paste coating film becomes 230 μm, and 100 An IR drying oven at a temperature of 1 ° C. was dried for 1 hour to form a phosphor paste coating film having a multilayer structure having a different filling density.

Depressions were formed on the surface of the coating film by the same method as in Example 6 to obtain a scintillator panel including a phosphor layer having a plurality of depressions on the surface, and the same evaluation as in Example 1 was performed.

(Example 22)

Apply the above-mentioned phosphor paste G with a die coater so that the thickness of the dried coating film becomes 50 μm, and then apply the above-mentioned phosphor paste A so that the total thickness of the phosphor paste coating film becomes 150 μm, and 100 An IR drying oven at a temperature of 1 ° C. was dried for 1 hour to form a phosphor paste coating film having a multilayer structure having a different filling density.

Depressions were formed on the surface of the coating film by the same method as in Example 15 to obtain a scintillator panel including a phosphor layer having a plurality of depressions on the surface, and the same evaluation as in Example 1 was performed.

(Example 23)

Apply the above-mentioned phosphor paste G with a die coater so that the thickness of the dried coating film becomes 50 μm, and then apply the above-mentioned phosphor paste A so that the total thickness of the phosphor paste coating film becomes 330 μm, and 100 IR drying oven at ℃ for 2 hours to form fluorescent light with multilayer structure with different filling density Body paste coating.

Depressions were formed on the surface of the coating film by the same method as in Example 5 to obtain a scintillator panel including a phosphor layer having a plurality of depressions on the surface, and the same evaluation as in Example 1 was performed.

(Comparative example 2)

Except that the height of the convex pattern was changed to 280 μm and the radius was changed to 70 μm, a scintillator panel was obtained by the same method as in Example 1, and the same evaluation as in Example 1 was performed.

(Comparative example 3)

A scintillator panel was obtained in the same manner as in Example 4 except that the radius of the convex pattern was changed to 10 μm, and the same evaluation as in Example 1 was performed.

(Comparative Example 4)

A scintillator panel was obtained in the same manner as in Example 4 except that the radius of the convex pattern was changed to 160 μm, and the same evaluation as in Example 1 was performed. In addition, periodic noise was observed in the obtained images.

(Comparative example 5)

A photosensitive paste was applied on a 100 mm × 100 mm glass substrate (sodium glass; thermal expansion coefficient 90 × 10 ^-7 (/ K), substrate thickness 0.7 mm) with a die coater so that the thickness of the dried coating film became 450 μm. Then, it was dried in an IR drying oven at 100 ° C. for 4 hours to form a photosensitive paste coating film. A mask (a chrome mask having a grid-shaped opening with a vertical and horizontal pitch of 194 μm and a line width of 20 μm) was passed through a photomask having openings corresponding to the desired partition wall pattern, and an ultrahigh-pressure mercury lamp with an exposure of 500mJ / cm ^{2 was used} . The obtained photosensitive paste coating film was exposed. Using a 0.5% by mass ethanolamine aqueous solution at 35 ° C as a developing solution, rinsing at a pressure of 1.5 kg / cm ^{2 for} 420 seconds to develop the photosensitive paste coating film after exposure, and further irradiating at 40 kHz while immersed in the developing solution. Ultrasonic waves of 100 W / cm ² were washed for 240 seconds at a pressure of 1.5 kg / cm ² , and then dried at 120 ° C. for 10 minutes to form a grid-like photosensitive paste pattern. The obtained photosensitive paste pattern was fired in air at 585 ° C for 15 minutes to form a grid-like partition wall having a cross-sectional shape as shown in Table 4.

Using a screen printing machine (manufactured by Microtek; using a phosphor blade; the screen is # 200SUS screen), the phosphor paste A was completely printed on the formed partition wall repeatedly, and vacuum-treated with a dryer to The IR dryer at 60 ° C. was subjected to heat treatment for 60 minutes, and then the overflowed phosphor paste was scraped off with a rubber spatula. Thereafter, the oven was dried in a hot air drying oven at 100 ° C. for 40 minutes to form a phosphor layer as shown in Table 5 to obtain a scintillator panel.

The obtained scintillator panel was set on an FPD (PaxScan3030; manufactured by Varian) to produce a radiation image detection device. The substrate side of the scintillator panel is irradiated with radiation having a tube voltage of 80 kVp, and Pax Scan3030 detects the luminous intensity of the scintillator panel 40B. As a result, a sufficient image can be obtained (hereinafter, the value of this luminous intensity is set to 100 for relative evaluation). In addition, through the MTF chart made of lead, the radiation of a tube voltage of 80 kVp was similarly irradiated from the substrate side of the scintillator panel, and the obtained image was subjected to data processing to calculate the MTF (hereafter, this MTF value is set to image clarity 100, For a relative assessment).

(Example 24)

A photosensitive paste was applied on a 100 mm × 100 mm glass substrate (sodium glass; thermal expansion coefficient 90 × 10 ^-7 (/ K), substrate thickness 0.7 mm) with a die coater so that the thickness of the dried coating film became 450 μm. Then, it was dried in an IR drying oven at 100 ° C. for 4 hours to form a photosensitive paste coating film. A mask (a chrome mask having a grid-shaped opening with a vertical and horizontal pitch of 194 μm and a line width of 20 μm) was passed through a photomask having openings corresponding to the desired partition wall pattern, and an ultrahigh-pressure mercury lamp with an exposure of 500mJ / cm ^{2 was used} . The obtained photosensitive paste coating film was exposed. A 0.5 mass% ethanolamine aqueous solution at 35 ° C. was used as a developing solution, and the film was rinsed at a pressure of 1.5 kg / cm ^{2 for} 420 seconds to develop the photosensitive paste coating film after exposure, and further irradiated in a state of being immersed in the developing solution. Ultrasonic waves of 40 kHz and 100 W / cm ² were washed for 240 seconds at a pressure of 1.5 kg / cm ² , and then dried at 120 ° C. for 10 minutes to form a grid-like photosensitive paste pattern. The obtained photosensitive paste pattern was fired in the air at 585 ° C for 15 minutes to form a grid-like partition wall having a cross-sectional shape as shown in Table 4.

Using a screen printing machine (manufactured by Microtek; using a fluorescent blade; screen # 200SUS screen), the phosphor paste A was completely printed on the formed partition wall repeatedly, vacuum-treated with a dryer, and then Take rubber The squeegee scraped off the spilled phosphor paste. Thereafter, the oven was dried in a hot air drying oven at 100 ° C. for 40 minutes to form a phosphor layer having a circular depression in the opening portion as shown in Table 5 to obtain a scintillator panel.

The obtained scintillator panel was set on an FPD (PaxScan3030; manufactured by Varian) to produce a radiation image detection device. The scintillator panel was irradiated with radiation having a tube voltage of 80 kVp from the substrate side, and the luminous intensity of the scintillator panel 24B was detected with PaxScan 3030. As a result, a relatively high luminous intensity such as 103 was obtained compared to 100 of the luminous intensity of Comparative Example 5. In addition, the lead image was irradiated with radiation of a tube voltage of 80 kVp from the substrate side of the scintillator panel through a MTF chart made of lead, and the resulting image was subjected to data processing to calculate the MTF. Shows higher values like 101.

(Example 25)

A scintillator panel was obtained in the same manner as in Example 24 except that the temperature of the hot air drying oven was set to 120 ° C. using the phosphor paste B described above, and the same evaluation as in Example 24 was performed. The parameters and evaluation results of the scintillator panel are shown in Tables 4 and 5. The same applies to the following Examples 26 to 40 and Comparative Example 6.

(Example 26)

A scintillator panel was obtained in the same manner as in Example 24 except that the temperature of the hot air drying oven was set to 120 ° C. using the phosphor paste C described above, and the same evaluation as in Example 24 was performed.

(Example 27)

Using the above-mentioned phosphor paste D, and setting the temperature of the hot-air drying oven to 140 ° C, the same method as in Example 24 was used to obtain The scintillator panel was evaluated in the same manner as in Example 24.

(Example 28)

A scintillator panel was obtained in the same manner as in Example 24 except that the temperature of the hot air drying oven was set to 200 ° C. using the phosphor paste C described above, and the same evaluation as in Example 24 was performed.

(Example 29)

A scintillator panel was obtained in the same manner as in Example 24 except that the phosphor paste C was used and the temperature of the hot-air drying oven was set to 160 ° C, and the same evaluation as in Example 24 was performed.

(Example 30)

Using the above-mentioned phosphor paste C, and setting the temperature of the hot air drying oven to 90 ° C. and drying it for 80 minutes, a scintillator panel was obtained by the same method as in Example 24, and was performed and implemented. Example 24 The same evaluation.

(Example 31)

In the same manner as in Example 24, a grid-like partition wall was formed on a 100 mm × 100 mm glass substrate. Using a screen printing machine (manufactured by Microtek; using a phosphor blade; the screen is # 200SUS screen), the above-mentioned reflective layer paste C was completely printed on the formed partition wall several times. The groove is filled with a reflective layer paste C. After that, vacuum treatment was performed with a dryer, and then the reflective layer paste overflowing from the groove was scraped off with a rubber doctor blade. Thereafter, it was dried in an IR drying furnace at 40 ° C. for 120 minutes, and a reflective layer having a thickness of 10 μm was formed on the bottom surface of each of the grooves partitioned by the partition wall.

Then, a phosphor layer was formed by the same method as in Example 24 to obtain a scintillator panel, and the same evaluation as in Example 24 was performed.

(Example 32)

In the same manner as in Example 24, a grid-like partition wall was formed on a 100 mm × 100 mm glass substrate. Using a screen printing machine (using a phosphor scraper; the screen is # 200SUS screen), the above-mentioned reflective layer paste A was completely printed on the formed partition wall several times, and filled in the groove separated by the partition wall. Reflective layer paste A. After that, vacuum treatment was performed with a dryer, and then the reflective layer paste overflowing from the groove was scraped off with a rubber doctor blade. Thereafter, the oven was dried in a hot air drying oven at 160 ° C. for 60 minutes, and a concave reflective layer having a thickness of 10 μm was formed on the entire surface of each groove separated by the partition wall.

Then, a phosphor layer was formed by the same method as in Example 24 to obtain a scintillator panel, and the same evaluation as in Example 24 was performed.

(Example 33)

A scintillator panel was obtained in the same manner as in Example 32 except that the thickness of the reflection layer was 30 μm using the above-mentioned reflection layer paste B, and the same evaluation as in Example 24 was performed.

(Example 34)

A scintillator panel was obtained in the same manner as in Example 32 except that the phosphor paste C was used and the temperature of the hot-air drying oven was set to 120 ° C, and the same evaluation as in Example 24 was performed.

(Example 35)

The scintillator panel was obtained by the same method as in Example 32 except that the phosphor paste D was used and the temperature of the hot-air drying oven was set to 140 ° C, and the same evaluation as in Example 24 was performed.

(Example 36)

A photosensitive paste coating film was formed on a 100 mm × 100 mm glass substrate in the same manner as in Example 24. Regarding the obtained photosensitive paste coating film, the mask was changed to a chrome mask having grid-shaped openings having a vertical and horizontal pitch of 127 μm and a line width of 15 μm, and the exposure amount was changed to 350 mJ / cm ² . Exposure was performed in the same manner as in Example 24. Using a 0.5% by mass ethanolamine aqueous solution at 35 ° C as a developing solution, and rinsing at a pressure of 1.5 kg / cm ^{2 for} 500 seconds, the exposed photosensitive paste coating film was developed and further immersed in the developing solution. After irradiating an ultrasonic wave of 40 kHz and 100 W / cm ² for 400 seconds, washing with a pressure of 1.5 kg / cm ^{2 was} performed, and then a grid-like partition wall was formed by the same method as in Example 24.

Then, a reflective layer was formed by the same method as in Example 32, and the fluorescent paste E was used, and the temperature of the hot-air drying oven was set to 140 ° C. Except that the fluorescent film was formed by the same method as in Example 26. Light body layer to get a scintillator panel.

This scintillator panel was set on an FPD (PaxScan 2520; manufactured by Varian), and a radiation image detection device was produced, and the same evaluation as in Example 24 was performed.

(Example 37)

Using a screen printing machine (using a phosphor blade; the screen is # 165SUS screen), the above phosphor paste F was further printed on the scintillator panel obtained in the same manner as in Example 35, and The dryer was vacuum-treated, and then dried in a hot air drying oven at 100 ° C. for 40 minutes to form a second phosphor layer as shown in Table 5. The phosphor layer was obtained by filling the phosphor powder with different density. The scintillator panel composed of a plurality of layers was evaluated in the same manner as in Example 24.

(Example 38)

A scintillator panel was obtained in the same manner as in Example 35 except that the phosphor paste G was used, and the same evaluation as in Example 24 was performed.

(Example 39)

Using a screen printing machine (using a phosphor blade; the screen is # 165SUS screen), the above phosphor paste H was further fully printed on the scintillator panel obtained by the same method as in Example 38 to The dryer was vacuum-treated, and then dried in a hot air drying oven at 80 ° C for 40 minutes to form a second phosphor layer as shown in Table 5. The phosphor layer was filled with phosphor powder with different density. The scintillator panel composed of a plurality of layers was evaluated in the same manner as in Example 24.

(Example 40)

The above paste for a buffer layer was coated on a 100 mm × 100 mm glass substrate (sodium glass; thermal expansion coefficient 90 × 10 ^-7 (/ K), substrate thickness 0.7 mm) with a 15 μm rod coater, dried, and then dried using an ultra-thin film. The high-pressure mercury lamp irradiated the entire surface at 500 mJ / cm ² to form a paste coating film for a buffer layer having a thickness of 12 μm.

Next, a photosensitive paste pattern was formed on this paste coating film for a buffer layer in the same manner as in Example 24. The glass substrate for forming the photosensitive paste pattern obtained in this manner was fired in air at 585 ° C for 15 minutes, and the paste coating film for the buffer layer and the photosensitive paste pattern were fired to form A glass substrate having a buffer layer and a grid-like partition wall having a cross-sectional shape as shown in Table 4.

The scintillator is obtained by the same method as in Example 32. The panel was evaluated in the same manner as in Example 24.

(Comparative Example 6)

A grid-like partition wall was formed on a 100 mm × 100 mm glass substrate by the same method as in Example 24.

Then, the phosphor paste F was used, except that a phosphor layer was formed by the same method as in Example 24 to obtain a scintillator panel, and the same evaluation as in Example 24 was performed.

Claims (7)

A scintillator panel is a scintillator panel having a substrate and a phosphor layer containing a phosphor powder, wherein the surface of the phosphor layer has 500 to 50000 recesses per cm ² , and the area of the opening portion of the recess A The thickness D is 500 to 70,000 μm ² , and the ratio D / T of the thickness T of the phosphor layer to the depth D of the depression is 0.1 to 0.9. For example, in the scintillator panel of claim 1, the distance P between adjacent recesses is a certain value in the range of 50-350 μm, and the maximum width W of the recessed opening is 30-300 μm. The scintillator panel as claimed in claim 1 or 2, further comprising a partition wall separating the phosphor layer. For example, the scintillator panel of claim 3, further comprising a concave reflective layer between the phosphor layer and the partition wall. For example, the scintillator panel of claim 1 or 2, wherein the phosphor layer is composed of a plurality of layers with different filling densities of the phosphor powder. A radiographic image detection apparatus includes a scintillator panel as set forth in any one of claims 1 to 5. A method for manufacturing a radiographic image detection device, comprising a scintillator panel according to any one of claims 1 to 5, and a radiographic image of a detection substrate provided with a photoelectric conversion element opposed to the depression of the scintillator panel. The manufacturing method of the detection device includes (A) a step of aligning the depression with the photoelectric conversion element, and (B) a step of bonding the scintillator panel and the detection substrate.